title: Role of endocrine and paracrine factors in the adaptation of bone to mechanical loading.
abstract: There appears to be no unique mechanically sensitive pathway by which changes in bone loading regulate bone mass and architecture to ensure adequate structural strength. Rather, strain-derived changes in bone cells activate a number of nonspecific strain-sensitive pathways (including calcium fluxes, prostanoids, nitric oxide, extracellular signal-regulated kinase, and sclerostin), the activities of which are modified by a number of factors (including estrogen receptors) for which this contribution is subsidiary to other purposes. The strain-sensitive pathways modified by these factors interact with a number of other pathways, some of which appear to have specific osteoregulatory potential (eg, the parathyroid hormone pathway), whereas others such as the Wnt pathway appear to be associated primarily with the response mechanisms of proliferation, differentiation, and apoptosis. The outcome of these multiple interactions are stimuli for local bone formation, resorption, or maintenance of the status quo, to maintain existing bone architecture or adapt it to a new mechanical regimen.
authors.affiliation: School of Veterinary Sciences, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK. jo.price@bristol.ac.uk
authors.forename: Joanna S
authors.initials: JS
authors.lastname: Price
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Gabriel L
authors.initials: GL
authors.lastname: Galea
authors.forename: Lee B
authors.initials: LB
authors.lastname: Meakin
authors.forename: Andrew
authors.initials: A
authors.lastname: Sunters
authors.forename: Lance E
authors.initials: LE
authors.lastname: Lanyon
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015519:Bone Density / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000235:genetics; D001842:Bone and Bones / Q000502:physiology*; D004702:Endocrine Glands / Q000502:physiology; D047628:Estrogen Receptor alpha; D005819:Genetic Markers / Q000235:genetics; D006728:Hormones / Q000502:physiology*; D006801:Humans; D051379:Mice; D019899:Paracrine Communication / Q000502:physiology; D010281:Parathyroid Hormone
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; D047628:Estrogen Receptor alpha; D005819:Genetic Markers; D006728:Hormones; D010281:Parathyroid Hormone; C422903:SOST protein, human